scsi: ufs: core: Add host quirk UFSHCD_QUIRK_MCQ_BROKEN_RTC

Some hosts do not implement SQ Run Time Command (SQRTC) register, thus we
need this quirk to skip the related flow.
Signed-off-by: Po-Wen Kao <powen.kao@mediatek.com>
Link: https://lore.kernel.org/r/20230612085817.12275-3-powen.kao@mediatek.comReviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/ufs/core/ufs-mcq.c

@@ -451,6 +451,9 @@ static int ufshcd_mcq_sq_stop(struct ufs_hba *hba, struct ufs_hw_queue *hwq)
 	u32 id = hwq->id, val;
 	int err;
 
+	if (hba->quirks & UFSHCD_QUIRK_MCQ_BROKEN_RTC)
+		return -ETIMEDOUT;
+
 	writel(SQ_STOP, mcq_opr_base(hba, OPR_SQD, id) + REG_SQRTC);
 	reg = mcq_opr_base(hba, OPR_SQD, id) + REG_SQRTS;
 	err = read_poll_timeout(readl, val, val & SQ_STS, 20,
@@ -467,6 +470,9 @@ static int ufshcd_mcq_sq_start(struct ufs_hba *hba, struct ufs_hw_queue *hwq)
 	u32 id = hwq->id, val;
 	int err;
 
+	if (hba->quirks & UFSHCD_QUIRK_MCQ_BROKEN_RTC)
+		return -ETIMEDOUT;
+
 	writel(SQ_START, mcq_opr_base(hba, OPR_SQD, id) + REG_SQRTC);
 	reg = mcq_opr_base(hba, OPR_SQD, id) + REG_SQRTS;
 	err = read_poll_timeout(readl, val, !(val & SQ_STS), 20,
@@ -494,6 +500,9 @@ int ufshcd_mcq_sq_cleanup(struct ufs_hba *hba, int task_tag)
 	u32 nexus, id, val;
 	int err;
 
+	if (hba->quirks & UFSHCD_QUIRK_MCQ_BROKEN_RTC)
+		return -ETIMEDOUT;
+
 	if (task_tag != hba->nutrs - UFSHCD_NUM_RESERVED) {
 		if (!cmd)
 			return -EINVAL;
@@ -576,6 +585,9 @@ static bool ufshcd_mcq_sqe_search(struct ufs_hba *hba,
 	u64 addr, match;
 	u32 sq_head_slot;
 
+	if (hba->quirks & UFSHCD_QUIRK_MCQ_BROKEN_RTC)
+		return true;
+
 	mutex_lock(&hwq->sq_mutex);
 
 	ufshcd_mcq_sq_stop(hba, hwq);

include/ufs/ufshcd.h

@@ -617,6 +617,12 @@ enum ufshcd_quirks {
 	 * Enable this quirk will disable CQES and use per queue interrupt.
 	 */
 	UFSHCD_QUIRK_MCQ_BROKEN_INTR			= 1 << 20,
+
+	/*
+	 * Some host does not implement SQ Run Time Command (SQRTC) register
+	 * thus need this quirk to skip related flow.
+	 */
+	UFSHCD_QUIRK_MCQ_BROKEN_RTC			= 1 << 21,
 };
 
 enum ufshcd_caps {